The camel is a large mammal noted for the characteristic humps on its back. True camels come in two varieties, dromedary, or one-humped, and Bactrian camels which have two distinct humps. Though native to Asia, there are now about 700,000 wild camels in Australia, from specimens released into the wild after being used to build railroads.
The camel is prized for meat, leather, milk and working abilities. Known for their hardiness, camels make excellent pack animals for long trips through rough terrain. Though capable of surviving many days without water, the popular concept that they store water in their humps is a myth. Instead, the hump provides a reserve of fat cells that can provide additional energy on long or tiring journeys. Their water-conserving abilities are facilitated by several physical adaptations, including the shape of their red blood cells and the ability to reabsorb perspiration and retain the fluid.
Bactrian and dromedary camels are similar in size, both reaching heights of approximately seven feet (2.1 m) at the top of their humps, and weighing between 900-1400 lbs (408-635 kg.) Depending on the season in which they become pregnant, the female camel gestates for between 12-14 months, usually resulting in the birth of one calf. At birth, a camel weighs approximately 66 lbs (30 kg) and will double its weight in less than a year. The average lifespan of a camel is between 50-60 years, though cows typically stop producing calves around age 20.
Camels and humans have a long history together; they are believed to have been domesticated by 2000 BC. Although also prized for their meat and milk products, camels are often used as beasts of burden or work animals, and have even been used in military action for cavalry. They have often been used for railroad building or construction projects in desolate locations, where horses or oxen would be overstressed by the environment.
The practice of using camels in work projects has lead to some interesting results. In the Southwestern United States, camels were used to help with mining, and later released into the wild deserts. Sightings of their descendants are common, though not always credible. Camels have clearly made a new home for themselves in the Australian outback, where an enormous population of wild dromedaries subsists and grows in the absence of large predators.
Although camels survive well in domesticated situations, the wild populations of some groups are dwindling due to loss of habitat and other environmental concerns. Despite a thriving population of over a million Bactrian camels in the world, only 1000 are believed to remain in the wild. While the domestication of camels is an important human resource, it would indeed be a shame to let the feral populations of these remarkably adaptive creatures die out.